Question

full solution send kro
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Answer 1

Answer:

9.9 can be written as (10-0.1)

(9.9)² =(10-0.1)²

using the formula (a-b)²=a²+b²- 2ab

(10-0.1)²= 100+0.01

-2(2*10*0.1)

=98.01

Answer 2

Step-by-step explanation:

9.9 can be written as (10-0.1)

(9.9)² = (10-0.1)²

by using the formula

(a-b)² = a² + b² -2ab

(10-0.1) = (10)²+(0.1)²-2(10)(0.1)

(10-0.1)=(100)+(0.01)

2(2×10×0.1)

= 98.01 is the answer